Question

quais as respostas das equações? exercício número 8

Answer 1

A) x+3=7
x=7-3
x=4

b)2x-5=x+4
2x-x=4+5
x=9

c)9-4x-4=x+7-1
-4x-x=7-1+4-9
-5x=1
x=-1/5

d)16x+5-3=-2x-15
16x+2x=-15-5+3
18x=-17
x=-17/18

e) -x+40=4x
-x-4x=-40
-5x=-40
x=-40/-5
x=8

f) 6(x+5)=x
6x+30=x
6x-x=-30
5x=-30
x=-30/5
x=-6

g)5(y-9)-3=-18-y
5y-45-3=-18-y
5y+y=-18+45+3
6y=30
y=30/6
y=5

h)10-6(z-8)=9+z
10-6z+48=9+z
-6z-z=9-48-10
-7z=-49
z=-49/-7
z=7

i)12+2n=9(n-7)-2
12+2n=9n-63-2
2n-9n=-65-12
-7n=-77
x=-77/-7
x=11

Se tiver algum erro avisa pq é tanto número

Answer 2

a) $x+3=7$

$x+3=7~\Rightarrow~x=7-3~\Rightarrow~\boxed{x=4}$


b) $2x-5=x+4$

$2x-5=x+4~\Rightarrow~2x-x=4+5~\Rightarrow~\boxed{x=9}$


c) $9-4x-4=x+7-1$

$9-4x-4=x+7-1~\Rightarrow~-4x-x=7-1-9+4~\Rightarrow~-5x=1~\Rightarrow~\boxed{x=-\dfrac{1}{5}}$

d) $16x+5-3=-2x-15$

$16x+5-3=-2x-15~\Rightarrow~16x+2x=3-5-15~\Rightarrow~18x=-17~\Rightarrow~\boxed{x=\dfrac{-17}{18}}$

e) $-x+40=4x$

$-x+40=4x~\Rightarrow~-x-4x=-40~\Rightarrow~-5x=-40~\Rightarrow~\boxed{x=8}$.

f) $6(x+5)=x$

$6(x+5)=x~\Rifghtarrow~6x+30=x~\Rightarrow~6x-x=-30~\Rightarrow~5x=-30~\Rightarrow~\boxed{x=-6}$.

g) $5(y-9)-3=-18-y$

$5(y-9)-3=-18-y~\Rightarrow~5y-45-3=-18-y~\Rightarrow~5y+y=45+3-18$

$6y=30~\Rightarrow~\boxed{y=5}$.


h) $10-6(z-8)=9+z$

$10-6(z-8)=9+z~\Rightarrow~10-6z+48=9+z~\Rightarrow~-6z-z=9-48-10$

$-7z=-49~\Rightarrow~\boxed{z=7}$.


i) $12+2n=9(n-7)-2$

$12+2n=9(n-7)-2~\Rightarrow~12+2n=9n-63-2~\Rightarrow~2n-9n=-63-2-12$

$-7n=-77~\Rightarrow~\boxed{n=11}$.